� Fully digital signal processing Voicing Equalizer � 40bit floatingpoint DSP devices � Separate digital filters for Voicing and Equalizersections � Wide-format color LCD panel allows direct writing ofresponse curve with stylus pen � 20 pattern memory � Real-timespectrum analyzer � Analog connection possible via option boards

Call up cursor pad to select frequency and adjust level by moving cursor right and left or up and down.

Fig. 1 DG-38 Block Diagram

DG-38 Features

Call up input panel for character input or editing

Create your ideal listening environment with a stroke of the pen theDigital Voicing Equalizer makes this dream a reality. Separate sound fieldcompensation (Voicing) and sound field creation (Equalizer) functionsimplemented using powerful DSP devices and advanced signal processingtechnology. Large, wide-format color display panel allows use of a styluspen to directly draw or modify a curve. Connection to analog componentspossible using option boards.

This somewhat unusual term was chosen to symbolize the advanced capabilities

of the DG-38. While this product is a full-fledged high-precision graphic equalizer in

its own right, it also incorporates a sophisticated system for automatic sound field

compensation. It divides the audible frequency range into distinct bands (voices),

and lets the user choose a target response curve that is then expressed (voiced)

by the unit through a process of precise measurement and adjustment steps. The

result is full control over frequency response characteristics at the listening position.

Through creative use of the capabilities offered by the DG-38, the scope of sound

reproduction in the home environment can be significantly enhanced. Get ready to

experience a new dimension of music enjoyment.

What is a "Voicing Equalizer"?

When wishing to reproduce high-qualityprogram sources with optimum fidelity,the characteristics of the entirereproduction chain including the speakersas well as the listening room itself have tobe taken into consideration. The DigitalVoicing Equalizer DG-38 was created withthis fact in mind. It embodies Accuphase'shighly advanced knowledge of digitalsignal processing technology for audioapplications. Latest high speed DSP chipsas well as HS-Link input and outputcapability make the DG-38 perfectlysuited to handle all high-quality programsources including SACD.Functionally, the DG-38 is divided into twoequalizing modules. The first is theVOICING module designed to providesound field compensation, and thesecond is the EQUALIZER module thatlets the user creatively and actively shapethe sound field. These central DSPfunctions are handled by four 40bit floatingpoint SHARC processors from Analog

Devices. Thedisplay of theDG-38 is as u p r e m e l ylarge, wide-format colorLCD that isconfigured as atouch panel. It lets you simply draw adesired frequency curve with the suppliedstylus pen and immediately hear theresults. Control of other functions is alsoeasily accomplished with this panel. Aspectrum analyzer function has beennewly incorporated, providing a visualrepresentation of the spectral content ofany source in real time.The DG-38 can be connected to otherdigital Accuphase components such asthe DP-100/DC-101, DC-330, DP-85, andDP-77 via the HS-Link interface. Analogcomponents can be accommodated byinstalling suitable analog input/outputoption boards.

� Fully digital Voicing Equalizer with 40bit floating pointDSP devices for digital signal processing.

� 192 kHz/24 bit input/output interface

� Two equalizing modules: sound field compensation(VOICING) and sound field creation (EQUALIZER)

� Large, wide-format color LCD panel (154 × 58 mm)

� Touch panel and supplied stylus pen•Allows direct drawing of response curve onscreen

•Cursor keypad can be called up for pinpointoperation and touchup

•Control functions by tapping or dragging symbolsdisplayed on screen

� 20 memory slots to store entire patterns includingtarget curve, pre-compensation curve, post-compensation curve, equalizer curve etc. Data setscan be given a name and called up or modified atany time.

� RS-232 connector for interfacing with a computer

� Sound field measurement microphone AM-28supplied

� Supplied RemoteCommander RC-30

Controls input selector,equalizer on/off, memoryrecall, memory numberup/down.

Supplied stylus pen can be used to draw anydesired response curve.

Sound field compensation (voicing)

Spectrum analyzer

Sound field creation (Equalizer)

Configuration

CONFIGURATION

Two main circui t as-semblies with four highspeed 40bit f loat ingpoint DSP chips, UltraJitter-Free PLL circuit,tone generator, HS-Link en-coder/decoder,digi tal input/outputconnectors etc.

The DG-38 has four mainoperation modes:"Voicing", "Equalizer","Analyzer", and"Configuration".Four buttons on the frontpanel are used to selectthe respective mode.

Because the DG-38 incorporates both measurement and adjustment functions,accurate sound field compensation can be carried out easily. 68 IIR typefilters with 1/6 octave spacing are used for measuring the sound field, andthe resulting data provide the basis for accurate compensation.

This screen gives access to various functions including microphone setup,target curve setup, auto compensation, display of frequency responsebefore and after compensation, and calling up or saving frequency responsecurves.

The spectral content of the input signal can be displayed on a spectrumanalyzer screen with 1/3 octave spacing, 35 bands, and real-time operation.

This function is entirely separate from the adjustment functions of the unit,allowing you to monitor peak levels in real time. Comparison of Voicing andEqualizer on/off condition and checking of right/left frequency distributionare also possible.

When power to the DG-38 is turned on, the Equalizer screen shown here appears.

In this mode, the user can create a desired sound field by drawing a frequencyresponse curve. This can be done with the supplied stylus pen directly on thedisplay screen. A cursor keypad is also available, for manually creating the curveor making adjustments. The values set using this screen are automatically readand applied by the digital filters.

The equalizer filter section uses 74 IIR + FIR hybrid type filters with 1/6 octavespacing. Because the digital filters for sound field compensation and sound fieldcreation are separate, equalization can be further modified after the sound fieldcompensation (voicing) curve has been established.

This screen lets you make environment and function settings, such asselecting the Voicing/Equalizer modes, controlling levels, left/right balance,screen brightness and contrast, screen data send etc.

Functions are activated directly on the screen with the stylus pen.

Advanced compensation functions VOICING application examples

Ultra Jitter-Free PLL circuit ~Accuphase original digital interface~HS-Link: High Speed Link

Flat

Speaker

Microphone

Power amplifier Preamplifier

For testing, the DG-38 outputs four warble tones of different frequencies simultaneously. These are heard as a combined sound.

The internal test signal generator of the DG-38 produces warble tones which are used to drive the speakers via the power amplifier. The sound travels through the sound field and is picked up by the microphone for sound field measurement.

DAI signal input Preambledetector

Phasecomparator

Preamble signal(pulse distortion removed)

Loopfilter

Divider

Master clock output

Principle ofUltra Jitter-Free PLL circuit HS-Link Block Diagram

The DG-38 automatically measures the sound field and provides accurate compensation based on target characteristics representingthe ideal sound field. Compensation may be performed using ��a preprogrammed standard reference curve, � an automaticallycreated target curve, or ��a freely created curve.

A dedicated sound field mea-surement microphone withcontrol led frequency re-sponse is supplied with theDG-38.The microphone is a 1/4-inchtype back-electret condensertype with ul t ra-thin dia-phragm, which assures linearresponse over a wide fre-quency range.

Setup screen for Voicing leveland channel, microphone set-tings, etc.

Ex. 2 Compensation with automatically created targetcurve

Ex. 1 Using preprogrammed standard referencecurve

Ex. 3 Compensation with freely created curve

The DG-38 comes with four preprogrammed reference curves:three curves with high-end rolloff (–1 dB, –2 dB, –3 dB peroctave) and flat response.

L/R channael characteristics example for performing soundfield compensation with the "flat" target curve. Peaks anddips caused by listening room acoustics and speakercharacteristics are evened out, resulting in approximatelyflat response.

If flat response was selected forcompensation

(Creating a curve that incorporates speaker and roomcharacteristics)

First, automatic measurement of characteristics beforecompensation is carried out.� Speaker and room characteristics (Separate measurement

for L, R or simultaneous L/R measurement is possible)� Individual speaker characteristics

Auto generat ion ofcurve for flat response+

Based on the measured characteristics beforecompensation, a target curve for achieving balanced L/Rresponse at the listening point is created automatically.The curve can be further modified on screen to reduce smallpeaks and dips.

Using the stylus pen, any desired target curve can becreated freely.

Auto compensation is performed based on the targetcurve. By comparing the characteristics before and aftercompensation, the difference can be easily checkedvisually as well as aurally.

Auto compensation is performed based on the createdtarget curve. By harnessing room characteristics andspeaker characteristics, it is possible to counter theeffect of standing waves and achieve well balancedcompensation for the right and left channels.

The operation of a D/A converter must be synchronized with the input signal.For this purpose, a phase-locked loop (PLL) circuit generates a master clockwhich is used as system reference. In the DG-38, the so-called Ultra Jitter-Free PLL circuit developed by Accuphase is used.As shown in the illustration, this circuit consists of a detector for the preamblecomponent (a kind of start marker for the L/R signal) and a voltage-controlledoscillator (VCO) using a quartz crystal element. The master clock producedby this PLL circuit is totally free from the effects of pulse distortion and jitter.

HS-Link is an ultra high-quality digital audio interface developed by Accuphase. It supportssend/receive verification for copyright protection. The LVDS (Low Voltage DifferentialSignaling) principle allows a single dedicated HS-Link cable to transmit signals usingadvanced formats such as 2.8224 MHz/1 bit or 192 kHz/24 bit. Conventional digitalformats are also supported. Because digital audio data are transmitted with utmostfidelity, the sound quality achieved by HS-Link is simply outstanding.

For balanced connection: AI2-B1 (2 slots)For unbalanced connection: AI2-U1 (1 slot)

For balanced connection: AO2-B1 (2 slots)For unbalanced connection: AO2-U1 (2 slots)

Connections between DG-38 and other components

Option boards that can be used in the DG-38

Digital Line Input/Output BoardDIO-OC1

HS-Link cableHDL-15

Line Input BoardAI2-U1

Balanced Input BoardAI2-B1

Line Output BoardAO2-U1

[Number of slots used: 1] [Number of slots used: 2][Number of slots used: 1]

[Number of slots used: 2][Number of slots used: 2]

Balanced Output BoardAO2-B1

Sound field compensation for all program sources input to DC-330

Connections to analog components

Connection example for use of DC-101 or other DAC

Connection of analog output and digital output to DG-38

Audio cable HS-Link cable

HS-Link cable

Optical fiber cable

Audio cable

Power amplifier

Left speaker Right speaker

75-ohm coaxial cable

Audio cablePreamplifier Power amplifier

Input board Output board

HS-Link cable

HS-Link cable

(supplied with DP-100)

or DP-85/DP-75V

75-ohm coaxial cable

Optical fiber cableAudio cable

Optical fiber cable

75-ohm coaxial cable

Preamplifier

Analog output

Digital componentsuch as CD transport

Digital component suchas CD transport, DAT or MD recorder

HS-Link cable

Optical fiber cable75-ohm coaxial cable Audio cable

Audio cable Preamplifier

Input board Output board

SACD transport CD transport, MD, etc. CD player, tuner, etc.

DI2-HS1installed(2 slots)

DO2-HS1installed (1 slot)

DI2-HS1installed inEXT DSP slot

DI2-HS1standard equipment

in DC-101(2 slots)

DIO-OC1 installedin EXT DSP slot(1 slot)

For balanced connection: AI2-B1 (2 slots)For unbalanced connection: AI2-U1 (1 slot)

For balanced connection: AO2-B1 (2 slots)For unbalanced connection: AO2-U1 (2 slots)

[ [

The DG-38 is a Voicing Equalizer with many functions. By incorporating it into an existing audio system,the entire reproduction chain including the speakers and the listening room can be measured andoptimized to achieve the best possible playback quality.

The DG-38 can be connected to digital components such as the DC-330, DP-85, or DP-77 (with DO2-HS1installed) via HS-Link. This provides full support for digital signals using various sampling frequencies,including the DSD signal of SACD sources and 192 kHz/24 bit signals. To connect analog components,separately available option boards can be installed which incorporate high-quality A � D converters thatkeep signal degradation to an absolute minimum.

� HS-Link, optical, and coaxial digital input/output connectors provided as standard equipment

� Input signal selector menu of DG-38 allows the user to choose HS-Link, optical, coaxial, or installedoption board

� Connection to analog components implemented via option boards

� Up to four option boards can be installed

Provides coaxial and opticalinputs and outputs.

* Supports sources with samplingfrequencies up to 96 kHz.

Serves for transmission ofdigital signal corresponding tothe HS-Link interface.

* Shielded twisted pair 8-conductorOFC cable (TIA/EIA568-A CAT.5)

* 3 m, 5 m, 7.5 m, and 10 m cablelengths are also available.

* Conventional high-level input

* Input signal is converted to 24-bit digital signal by on-boardA/D converter.

* Internal sampling frequency selector should be set to 96 kHz.

�Digital boards �Analog boards * The analog input signal is converted to a digital signal by an on-board A/D converter. Thedigital output signal is converted to an analog signal by an on-board D/A converter.

* Conventional high-level output

* On-board high-precision D/A converter supplies analog outputsignal.

* D/A converter type: 192 kHz (max.), 24 bit, MDS Plus.

* Set EXT DSPbutton on DC-330to ON forconnection toDG-38

Analogcomponent

such as tuneror CD player

DP-100 or DP-85transport output,

DP-77 withDO2-HS1 installed

DP-100 orDP-85transportoutput, DP-77with DO2-HS1installed

Example 1: DG-38 connected to REC/PLAY jacks of RECORDER loopExample 2: DG-38 connected between preamplifier and power amplifier (see below)

* EXT DSP of DC-101 OFF:Sound field compensation for DP-100 connected with HS-Link

* EXT DSP of DC-101 ON:Sound field compensation for source connected with coaxial cable oroptical fiber

� Example for connecting the output of adigital component such as a SACD/CDtransport and the analog output of acomponent such as a CD player directly tothe DG-38compensation for sourceconnected with coaxial cable or optical fiber

�For unbalanced connections

�For balanced connections

�For balanced connections

�For unbalanced connections

HS-Link cable

HS-Link cable

Left speaker Right speaker

Audio cable

Audio cable

Audio cable

Multi-amped system to handle all sources input to DC-330

Audio cable High rangepower amplifier

Low rangepower amplifier

DI2-HS1 (2 slots)

DO2-HS1installed

DO2-HS1installed inOUTPUTS slot

DI2-HS1 installed inEXT DSP slot (2 slots)

Connection example for multi-amped system with DG-38 DF-35 Multi-amped system with DG-38 between DC-330 and DF-35

Multi-amped system with analog preamplifier and DG-38/DF-35

Optical fiber cable

75-ohm coaxial cable

Power amplifier

Power amplifier

DIO-OC1 installed in EXT DSP and OUTPUTS slots

DIO-OC1 (1 slot)

Optical fiber cable75-ohm coaxial cable

Analog outputAnalog preamplifier

Set switch on boardto 96 kHz

For balanced connection: AI2-B1 (2 slots)For unbalanced connection: AI2-U1 (1 slot)

DG-38 Guaranteed Specifications

• Specifications and design subject to change without notice for improvements.

A0305Y PRINTED IN JAPAN 850-0130-00 (AD1)http://www.accuphase.com/

Direct HS-Link connection of DG-38 � DC-330 � DF-35 createsmulti-amped system with support for SACD sources.

�HS-Link connection handles all sources that are inputto the DC-330, including SACD.

* Set EXT DSP button of DC-330 to ON for sound fieldcompensation of input sources.

* OUTPUTS slot of DC-330 � DF-35 input* All connections made with HS-Link cable

�When connection to DG-38 is madevia coaxial or optical fiber cable,sources input to DC-330 withsampling frequencies up to 96 kHzare supported.

�Output of analog preamplifier is connected to DG-38 for sound field compensation,and digital output of DG-38 is sent to DF-35.

�� Front panel

�� Rear panel

Remarks� This product is available in versions for 120/230 V AC. Make sure that the voltage shown

on the rear panel matches the AC line voltage in your area.� The shape of the AC inlet and plug of the supplied power cord depends on the voltage rating

and destination country.� Microsoft ® and Windows ® are registered trademarks of Microsoft Corporation in the

U.S. and in other countries.

� Display� Voicing button� Equalizer button� Microphone input jack� Power switch� Analyzer button� Configuration button

� Digital inputsHS-Link COAXIAL OPTICAL

Digital outputsHS-Link COAXIAL OPTICAL

RS-232 interface� AC power connector�

�

[Guaranteed specifications and standard compliance are measured according to EIAJ CPR-2101.]

� Voicing 1/6 octave 68-band IIR filter Adjustment range ±12 dB

� Equalizer 1/6 octave 74-band hybrid IIR filter + FIR filter Adjustment range ±12 dB

� Measurement signal Warble tones

� Frequency Response Direct drawing with stylus pen or input with cursor keypadCurve Input Principle

� Spectrum Analyzer 1/3 octave, 35-band real-time typeDisplay level: +20 dBFs to –100 dBFs (4 ranges, switchable)

� Reproduction Frequency 0.5 - 50.000 Hz +0 –3.0 dBResponse (For sampling frequency 2.8224 MHz or 192 kHz)

4.0 - 20,000 Hz +0 –0.3 dB

� Gain +6 to –90 dB, variable

� Digital Inputs HS-Link Connector type: RJ-45 (dedicated HS-Link cable)OPTICAL Format: EIAJ CP-1201/AES3 compliantCOAXIAL Format: EIAJ CP-1201 compliantSampling frequency: 32 kHz, 44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz

(16 to 24 bit 2-channel PCM)[With HS-Link only]

176.4 kHz, 192 kHz (16 - 24 bit 2-channel PCM)2.8224 MHz (1 bit 2-channel DSP)

� Digital Outputs HS-Link Connector type: RJ-45 (dedicated HS-Link cable)OPTICAL Format: EIAJ CP-1201/AES3 compliantCOAXIAL Format: EIAJ CP-1201 compliant

� OS Microsoft® Windows® CE operating system

� Power Requirements AC 120 V / 230 V, 50 / 60 Hz(Voltage as indicated on rear panel)

� Power Consumption 23 watts

� Maximum Dimensions Width: 475 mm (18-7/10")Height: 150 mm (5-7/8")Depth: 395 mm (15-9/16")

� Weight 12.3 kg (27.1 lbs) net17.3 kg (38.1 lbs) in shipping carton

SuppliedAccessories

� Stylus pen� Microphone cable� Coaxial digital cable (2)� Remote Commander RC-30

� Microphone AM-28� Microphone holder� HS-Link connector housing (2)� AC power cord

House the supplied stylus pen here

Option boardexpansion slots